Kidde Standard Inconnectable Wiring
All Kidde interconnectable hard wired alarm come with a 3 wire connection. If interconnect wiring is already setup in your home, you will not need to do any installation for wiring. Kidde currently uses a 3 wire connection that is in the shape of a triangle (see pics below). Some manufactures have a connection in the shape of a line. If you currently have a connection in the shape of a line (see above), you may may use a adapter to connect to alarm configurations identified on the specifications sheet above. YOu may also chose to replace the wires into the provided connectors which would not require an adpater. Intallation instructions are provided with the alarms.Quick Convert Adapter Model# KA-B, KA-F
For use with Kidde Models: 1235, 1275, 1276, 1285, PE120, PI2000, KN-COSM-IB Description The quick convert adapter allows the installation of a new Kidde alarm to an existing competitive wiring harness. This allows for easy installation when replacing the specified smoke alarm brands with a Kidde product. The smoke alarm adapter also allows the specified approved brands and models to be interconnected with other Kidde product. Installer Friendly Features Model KA-B For use with First Alert� and BRK� wire in smoke alarms. The KA-B can only be used when replacing First Alert� models: SA4121B, and BRK� models: 4120, 4919, 5919, 86RAC with plug in connector, manufactured before June 1, 2003. Model KA-F For use with Firex� wire in smoke alarms The KA-F can only be used when replacing Firex� models: FADC, ADC, and AD, manufactured before June 1, 2003. Adapters can be used when replacing First Alert,� BRK� and Firex approved models without any rewiring. Configurations 1275-9952, 1275-9969, and 900-0153-012 include both adapter models.

Interconnect Compatibility with Firex and First Alert/ BRK
This information if provided to inform customers that the below models of Kidde smoke alarms are tested and do communicate and interconnect with the following make/models:

First Alert and BRK models; SA4121B, 4120, 4919, 5919, AND 86 RAC. These models have interconnect compatibility with the kidde alarm models; 1235, 1275, 1276, 1285, PE120, PI2000, i12020, i12040, i12060, i12080 AND KN-COSM-IB and RFSM AC/DC.
Quick Convert Adapter Model# KA-B, KA-F For use with Kidde Models: 1235, 1275, 1276, 1285, PE120, PI2000, KN-COSM-IB Description The quick convert adapter allows the installation of a new Kidde alarm to an existing competitive wiring harness. This allows for easy installation when replacing the specified smoke alarm brands with a Kidde product. The smoke alarm adapter also allows the specified approved brands and models to be interconnected with other Kidde product. Installer Friendly Features Model KA-B For use with First Alert� and BRK� wire in smoke alarms. The KA-B can only be used when replacing First Alert� models: SA4121B, and BRK� models: 4120, 4919, 5919, 86RAC with plug in connector, manufactured before June 1, 2003. Model KA-F For use with Firex� wire in smoke alarms The KA-F can only be used when replacing Firex� models: FADC, ADC, and AD, manufactured before June 1, 2003. Adapters can be used when replacing First Alert,� BRK� and Firex approved models without any rewiring. Configurations 1275-9952, 1275-9969, and 900-0153-012 include both adapter models.